1. Field of the Invention
The present invention relates to an optical communication module, an optical receiving module, a sleeve, an optical part, and a method of making the optical part.
2. Description of the Related Art
European Patent Publication No 826998-A2 discloses an optical receiving module in which a short ferrule is incorporated, whereas the short ferrule has an internal optical fiber therein. The optical receiving module is optically coupled to an output end of an optical fiber, whereas this end abuts against the input end of the internal optical fiber in the short ferrule. Light is emitted from the optical fiber, and this light is incident on the internal optical fiber contained in the short ferrule. On the other hand, the short ferrule has a tilted face at the output end thereof. When light travels across an interface between optical media having respective refractive indices different from each other, transmitted light and reflected light is created at this interface from the traveling light (e.g., the optical fiber has a refractive index of 1.46 whereas the atmosphere has a refractive index of 1.0). In the optical receiving module disclosed in the above-mentioned publication, the tilted face of the output end of the short ferrule serves to restrains the light reflected at the output end of the short ferrule from returning to the short ferrule and optical fiber.